In freezing environments a problem exists in storing and transporting particulate materials, e.g., gravel, coal and the like, in metal containers, e.g., dump trucks, railroad cars and the like. Also, metal parts such as railroad switches and scales tend to freeze up under such conditions. When the moisture on the surface of particulate materials freeze, the ice which is formed acts as a strong adhesive which causes the particulate materials to form a solid and bond to the interior surfaces of such containers and carriers, thus making it difficult to completely clean the surface. Moisture may come in contact with the interior of such containers and carriers through natural sources such as being carried on the particulate materials, melting snow, rain and the like.
It is obvious that particulate materials, such as coal, when frozen into a container can cause serious problems in unloading and the like. Many approaches to solving the problem have been suggested. For example, sodium chloride and calcium chloride have been added to moist coal, as it is being loaded, with some success.
Attempts have been made to coat the inside of the containers and carriers with a hydrocarbon oil, for example, kerosene. This has provided some help in preventing the particulate material from freezing to the interiors. However, it has not met with complete success. Other techniques have been tried for melting the frozen water, also without complete success.